Compact-Flash有著體積小、重量輕、防震、低耗電、不具揮發性等優點，相當適合做為嵌入式系統環境的資料儲存媒體。如今Compact-Flash已經在嵌入式多媒體應用上已獲得廣泛的使用，然而大多數的Compact-Flash都是使用FAT file system (FATfs)，FATfs有著簡單、容易實做、支援度廣的優點，但是卻有著效能上的問題。對於多媒體應用來說，存取效能卻是最重要的課題。所以本論文的目標就是實作高效能的FAT檔案系統，我們朝向三個方面進行，分別是：分離式快取、有效利用Compact-Flash忙碌等待時間(busy waiting time)、以及直接大量存取與減少處理器負擔。
　　我們將快取區分為三種快取：Data Cache，FAT Cache，FDE Cache。檔案系統可透過Data Cache存取ㄧ般資料、透過FAT Cache存取檔案分配表(File Allocation Table)、透過FDE Cache存取FAT目錄結構(FAT Directory Structure)。我們利用CF忙碌等待時間計算下ㄧ個叢集號碼與補充可用空間，並將記憶體複製的動作延遲到下一次的CF忙碌等待時間執行。當大量存取時，我們使用處理器直接存取CF而不透過快取存取，我們並減少除法運算以降低處理器的負擔。
　　測試結果顯示，在讀取時，利用CF忙碌等待時間的確能有效減少反應時間，但寫入時卻不行。另外，我們的系統在反應時間上有不錯的表現，且也有較低的CF讀寫次數。

　　Compact-Flash has the advantages of small size, lightweight, shock resistant, low power consumption, and nonvolatile, thus, it shows promise for being used in storage device for embedded systems. Nowadays, Compact-Flash has been used widely in embedded multimedia applications. However, most file systems on Compact-Flash are FAT file system(FATfs), FATfs is simple, easy to implement, and widely-used, but it’s performance is poor. Performance is the most important issue for multimedia applications. So, the goal of this thesis is to implement a high performance FAT file system, we focus on three directions: 1.separate cache, 2.exploiting Compact-Flash busy waiting time, 3.direct access for burst read/write and reduce CPU loading.
　　We separate cache into three caches: Data Cache, FAT Cache, FDE Cache. File system can access ordinary data through Data Cache, access File Allocation Table through FAT table, and access FAT Directory Structure through FDE Cache. We use CF busy waiting time to prefetch next cluster number and replenish free clusters, and delay the execution of memory copy to the next CF busy waiting time. When large amount of access, we use CPU to access CF directly instead of accessing through cache, and we also reduce division operation to reduce CPU loading.
　　Experiment result show that exploiting CF busy waiting time can reduce response time in read operation but fail in write operation. And our system has good result in response time test, and has lower CF read/write times.

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